A refrigerator is an appliance used for storing food or other times at low temperature, e.g., in a frozen state or refrigerated. The interior of the refrigerator is cooled by cold air circulating therein.
The refrigerator includes a heat exchanger configured to supply cold air into the refrigerator. Cold air can be continuously generated as a refrigerant recycling through compression, condensation, expansion and evaporation. Cold air supplied in the refrigerator is uniformly distributed by convection.
The heat exchanger may be installed at a side of the refrigerator and isolated from the storage spaces such as the refrigeration compartment and the freezer. For example, compression and condensation processes may be performed by a compressor and a condenser disposed within a machine compartment located at the lower back side of the refrigerator. By evaporation of a refrigerant, the refrigerant may absorb heat from ambient air surrounding the evaporator and thereby produce cool air.
The refrigerator includes a main body having a rectangular parallelepiped shape with a front opening. A refrigeration compartment and a freezer may be disposed in the main body. A refrigeration compartment door and a freezer door may cover the front of the main body. Drawers, racks, storage boxes and the like for sorting and storing different kinds of items may be disposed in the internal storage space of the refrigerator.
In general, a top-mount-type refrigerator has a freezer located on top of a refrigeration compartment. In contrast, a bottom-freezer-type refrigerator has a freezer located under the refrigeration compartment. This enables a user to conveniently access the refrigeration compartment. On the other hand, this may be inconvenient for a user to access the freezer, if the user has to bend or lower his or her body to reach, e.g., to take out ice pieces.
Some bottom-freezer-type refrigerators have an ice dispenser disposed in a refrigeration compartment door located at the upper side of the refrigerator. In this case, an ice-making device for supplying ice may be disposed in the refrigeration compartment door or the interior of the refrigeration compartment.
Ice-making devices may be classified into indirectly-cooled ice-making devices (which use cold air to freeze water into ice), and directly-cooled ice-making devices (which rely on heat transfer between a refrigerant pipe and an ice tray to freeze water). The directly-cooled ice-making devices have much higher cooling efficiency.
However, in a directly-cooled ice-making device, frost often undesirably forms on the refrigerant pipe and the ice tray. The frost can impair the performance and efficiency of the ice-making device.